Page 134 - CW E-Magazine (17-6-2025)

Point of View

CTO). The economics of ethylene produced by CTO/MTO come somewhere between the ethane- and naphtha-based crackers, though
it depends on the price of crude oil. CTO is energy-intensive, and the economics will worsen should a carbon penalty be imposed by
regulators. While a significant portion of new ethylene capacity in China in recent times has been based on this route, no other country
has gone down this path.

Reducing the carbon footprint
The carbon footprints of ethylene crackers vary, depending on the feedstock mix that goes into them, but typically between 1.4-1.8
tonnes of carbon dioxide (CO ) is emitted per tonne of ethylene produced. Considering global ethylene production in 2023 was around
2
177-mt, this olefin alone represents a carbon footprint of around 260-mt of CO .
2
The approaches to lower this footprint can be broadly classified into three categories: change in the feedstock that goes into a cracker;
modifications in the process, including through electrification (with the electricity being renewable or non-fossil based); and capture of
the CO released and its sequestration.
2
Among the feedstock switches is a one based on bioethanol, and is now practiced in a few plants, notably in Brazil where sugarcane-
based ethanol is cheap and abundant. India too has one bio-ethylene plant based on this route (a few have closed) to make EO/MEG.
Expansions have been limited by poor economics vis-à-vis conventional routes and is expected to stay a niche for making PE and EO/
MEG, despite its lower carbon footprint.

Recent efforts to address the mounting problem of plastic waste via chemical recycling is providing another option to lower the carbon
footprint of crackers. The most common route involves converting plastic waste into a hydrocarbon-containing pyrolysis oil, which can be
upgraded to serve as co-feed to a naphtha cracker. The technology is still in its early stages and there are no crackers that purely run on
this waste-derived feed, but it does afford olefins with a lower carbon footprint. A ‘mass balance’ approach is a useful way of allocating
the benefits of circularity so derived to a fraction of this output.

Another decarbonisation effort involves electrification of crackers – substituting the high thermal energy needed with renewable electricity
(solar and wind) – providing up to 95% reduction in carbon footprint. The first projects to do this are in demonstration stage and the results seem
encouraging. Deployment at commercial scale is a couple of years away and ramp up through retrofitting of existing crackers and new builds
will have to wait till the next decade. An interesting development, still in the planning stages, involves coupling a cracker to a Small Modular
Nuclear Reactor, as the power needs and supply can be balanced.

Carbon capture and sequestration (CCS) is an option as well but will only work in regions geographically lucky to have nearby
underground reservoirs or depleted oilfields (India does not seem to be).

But decarbonising ethylene production is not just a technical challenge; it requires consistent policy and fiscal support. Recent
developments on this front are not encouraging and a world-scale ethylene project in Canada by an industry major – touted as a ‘net-zero’
cracker – has been put on the back-burner largely due policy uncertainties. Given the size of the ethylene industry, and the technological and
commercial challenges, transitioning its production to a more sustainable path, will be a slow and challenging process.

Shifting dynamics
While global ethylene capacity has continued to grow steadily, and will continue to do so, a radical shift in world order has taken place.
Europe, once the world’s leading regional producer, with more than a quarter of capacity, has been overtaken by the Middle East, US and
Asia (excluding China). Subsequently, China overtook everyone, with an unprecedented rate of growth. Fast forward to 2040, and China
is still expected to still dominate while striving for self-sufficiency at the ethylene derivative level and continuing to invest in ethylene
manufacturing.

Elsewhere in Asia, things have turned more challenging, and producers are grappling with declining or near-zero growth domestic
markets, and reduced options for exports.

India remains an exception and will continue to need at least one world-scale cracker per year for the foreseeable future.
Ravi Raghavan

134 Chemical Weekly June 17, 2025

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